Automatic gun



C. C. BLACKMORE.

AUTOMATIC GUN.

APPLICATION FILED Nov. 191s.

Patented Aug. 3l, 1920.

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@www SYM I l l I I! L @mic C. C. BLACKMOR.

AUTOMATIC GUN.

APPLICATION vFILED Nov.1, 191s.

Patented Aug. 31, 1920.

4 SHEETS-SHEET 2.

C. C. BLACKMORE.

' AUTOMATIC GUN.

APPLICATION `FILED Nov. I. Ism.

Patented Aug. 31, 1920.

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c. c. BLACKMORE.

AUTOMATIC GUN.

APPLICATION FILED NOV. 7. 1918.

1 35 1 ,O1 7, Patented Aug. 31, 1920.

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CHARLES C'. BLACKMORE, vOF DAYTON, OHI

.AUTOMATIC GUN.

App1cation filed November 7, 19178. Serial No. 261,446.

To all'whom t may concern:

Be it known that I, CHARLESv C. ABLAYCK-- MORE, a citizen of the United States, residing at Dayton, in the county of Montgomery 5 and State of Ohio, have invented certain new and useful Improvements in Automatic Guns, of w'hich the following is a.specifica tion, referencebeing had therein to the accompanying drawing. This invention relates to improvements in automatic guns.

These improvements consist in a, novel arrangement of twin guns, or two duplicate gun mechanisms, in such. a manner as that `fthe reacting force of discharge of one of the guns may be utilized to load and ire the other gun. f

' By such an arrangement of twin guns and utilization of the reacting force resultant from the discharge thereof, the rapidity of firing may be .greatly increased as each 1 single gun is Icapable of being fired as rapidly as itl would be,if' used independently. CombiningL two gunsin this Vmanner with "Vv the same operating m/chanism results in ef- -fect in increasing the rapidity of firing to .approximately twice that of a single automatic gun.

l T he twin guns are associated and operated I ina manner that permits of small compact proportions of the mechanism, the minimum in`A size and weight being ma-intained. The construction consistsof simple, but highly efficient mechanism, only the minimum of gpartsbeing used. Practically all operablel parts have positive movements,the use of springs being limited to parts where breakage is not likely to occur.

The entire mechanism. is designedand or- 4@ ganized in a manner to provide for easy dismantling and reassembling of theparts so i I .that an ordinary mechanic or soldier inl structed in the use of the gun will experience no trouble in keeping it in normal working condition.

In size and weight the combined guns compare favorabl with the latest improved automatic guns o like caliber and therefore Y without any relative dlsadvantage wlth rehave the saine advantages with respect to portability and general adaptability to conditions of use.

The advantages of such an arrangement of two guns with loading and firing mechanism common to both guns-will readily be apparent when it is understood that aside from dependability vand, durability, tlig .into each barrel after it is fired servesto prime requisite for an automatic gun, is the -rapidity with which it may be fired.

It is obvious, therefore, that duplicate guns so arranged will fire twice as rapidly as a single gun, all other conditions being equal and will be twice as effective yas the single gun with the added advantage of being operable by one man instead of two.

The twin guns are also peculiarly adaptable for special uses such as in armored carsx or tanks and aeroplanes where it is desirable to equip'wijthguns heavier than rifle size, the constructionbeing such as is readily adaptable to all sizes of guns using fixed ammunition.

An important feature of` my invention consists of improved means for air cooling the guns in addition to the usual means employed for cooling the barrels externally in guns of this character. I have evolved an arrangement whereby a current of air is forced into each barrel and through the barrel each time the barrel is fired, thus aiding materially to prevent excessive heating 80 of the mechanism during severe usage and contributing to the effectiveness with which the guns may be operated and also to the prolongation of the life of the mechanism.

In view of the double capacity of the guns it is obvious, of course, that to obtain the maximum rapidity of firing of a single au- Atomatic gun, it is necessary only to I'ire. each barrel-half as rapidly as the single gun to attain to an equal effectiveness. VThusythe twin-(guns will discharge projectiles as rapidly as the maximum speed of a single barrel gunv with a greatly reduced tendency of the barrels' to become heated.

Uponthis equal basis of firing the advantagesl are decidedly in favor of the duplicate guns because the tendency to overheat the barrels and mechanism is minimized. The rapidity of firing the duplicate guns may be increased, of course, until each barrel is firing at the maximum speed of a single automatic gum-the two barrels. firing at twice the speed of a single gun Y discovered in the evolution of my invention fY for cooling thgun barrels by forcing air further aid in preventing overheating thereof, so that at the maximum speed of firing the tendency of the guns to overheat ismaterially reduced. v

, In the accompanying drawings I have illustrated the preferred form of construction of my invention, `wherein the recoil of each barrel` is directly employed to clear itself each time after firing and to load and fire the other barrel. To this end I utilize the gases which result from the discharge of the explosives to increase the force of the recoil in order that there maybe ample force to actuate the loading and firing mechanism. The two forms of construction shown in the drawings are known as recoil operated guns and gas operated guns.

The normal arrangement of the gun barrels of my invention is to arrange the barrels longitudinally of eachother, but the general construction and operation of the mechanism is such as may be 'readily adapted to an arrangement ofthe barrels at any angular relation to each other or to barrelsv capable of angular `adjustment independent `of each other'.

Also as far as I am aware`I am the first to employ means for forcibly discharging air into the gun barrel after each discharge of firing.

While I have described the gun Aas. a twin gun, it is obvious that aV greater number of gun mechanisms may be associated 'in the same way,the arrangement of the mechanism being such that the firing of one gun will act to clear itself after each discharge thereof and to load and fire anothergun in a fixed sequence of operation. I l

It is also obvious that my invention is n ot limited to guns for rifle firing. The principle of the invention is equally applicable to all kinds. and sizes of breech loading guns in which cartridges or shells are used for loading.

Referring to the drawings, Figure 1 is a plan view of the gun, showing in dotted .lines the .limits of movement of the gun barrels; Fig. 2 is a plan view of the loading and firing mechanism with the top plate of the frame removed; Fig. 3 is a longitudinal sectional view of the mechanism taken on the line 3-3 of Fig. 2; Fig. 4 is a detail of part of the air cooling system; Fig. 5 is asectional View through one of the gun barrels; Fig. 6 is'a sectional View of the gas pressure chamber, gun barrel and tube; Fig. 7 is a longitudinal, sectional view of a modified form of construction wherein the gas resulting from liringthe guns is utilized by direct-connections to actuate the loading and firing mechanism.

- gun.

i bottom of th/e frame.

In the drawings, 1 is a horizontal frame member in which the loading and firing mechanism is mounted. The frame is of such a construction as is readilyv adaptable to either the mounted or portable type of of integral, the top plate 2 and ends 3 being secured `thereto in any suitable manner. rIhe mechanism within the frame is placed upon the bottom th reof. When the top plate ,is removed all ty e mechanism is The fiat horizontal frame is prefer- Y ably made with the bottom and sides there fully exposed and any part thereof may Y be readily adjusted or removed.

Special attention has been given in the design Aof the frame and the mechanism contained therein to simplicity of construction, ease. of adjustment and `reassembly, all the parts being readily accessible, so that an ordinary layman instructed in the use of the gun will experience no difficulty in dismantling and reassembling the'mechanisrn.

The guns are of vequal caliber and comprise duplicate mechanisms throughout' In ,describing their ponstruction and operation therefore, only one gun unit vwill vbe described, it being understood-.that'ithe vdescription applies' equally-,to 'theconstruetion and operation` of each gun.'l .l

Supported by the. frame'between the top and bottom 5 thereof is thef'gun barrel iwhich, in' the preferred form of'construction, is provided with an extension'5Whi'ch forms part ofthe receiving mechanism of4 the gun and is movably supported on the The extension 5 is fixed to the gun barreland is lnovablethere1 fore with the longitudinal recoil of the` barrel'when the gun is fired and also movable with the' barrel when the same is returned to' firing position after each 'recoil thereof.

The expansion 5 slides in guideways 6 formed in the bottom of the frame 1 and extending substantially the entire length 'of the frame. The member 5 is provided with tire length of said member and terminating at its forward end vin a head or cross wall 8 tovwhich the barrel 4 is rigidly secured.

Operable in the guideways 7 is a breech bolt 9 provided with a guideway 10 extending substantially the entire length thereof and terminating in transverse end walls 11 guideways 7 extending substantially the e'nand13 and having a central transverse wall 12. Rigidly secured to the breech bolt is a rack 14 extending substantially the entire -length v.of the breech bolt along the upper edge thereof; the purpose of which will presently be explained.

Movable in the guideway 10 is a firing pin 15 which is slidably supported in an aperture extending through the central wall 12 of the breech bolt 9 and l`by an enlarged end portion 16 which has a sliding lit in the guideway. Between the end 16 and the wall 12 and surrounding the firing pin is a spring 17 which is compressed against the wall 12 and exerts pressure against the enlarged` end 16 when the firing bolt is setrinl operative position.

Secured to the rear end of the firing pin of the enlarged portion 16 of the firing pin -is provided with a point 22 which projects through the end wall 13 of the breech' bolt 9 and strikes the firing cap of the vcartridge when the vfiring pin is released.

Also pivotally mounted upon the member 5 adjacent to and to the rear of the latch 20 is a sear or locking device 23 for the breech bolt which also acts to trip the latch4 20 to release the firing pin when the mechanism isclosed ready for irin Attached to the sear 23l on the under si e thereofis a stud 24 coacting withA a slot 25 in the bottom of the frame 1. .The slot consists of an angular portion 26 and a longitudinal portion 27 which act, respectively, through the stud 24 to move the sear into and out of locking engagement with the breech-bolt and tripp1ng relation with the latch 20; also to hold 97, the rack and slide thus being providedV the sear out of operative relation during 'an interval off the firing operation.

Explanation will now be made of -the mechanism which serves to combine the `twin guns and to control them in fixed sequence of automatic operation.

To this end the breech bolts 9 are each provided with the racks 14 to which reference has been made. The extensions 5 of the receiver mechanism are also each provided with racks 94 loosely secured to' the mem.- bers 5 by slots 95 and 96 and retaining studs with a rlimited amount of longitudinal movement relative to each other, the longitudinal movement of the racks 94 permitted by the slots 95 and 96 provides a slight pause in the mechanism at lthe beginning and endk of each firing action, thus permitting a novel arrangementu to cool Kthe barrels whichv will be described herein in detail, to function properly, and also serves to retain the racks constantly in full mesh with the gear 100 and acts further to prevent jamming of the mechanism.

Secured to a vertical shaft 98 having bearings in the upper and lower wallsvof theframe 1 are gears 99 and 100 meshing,

respectively, with racks 14 and 94 and 'serving therefore to unite the gunmechanisms in the reciprocal action and in lixed sequence of automatic operation. The mecha nisms are so arranged that the. respective functions of operation occur at opposite intervals of time, the nfiring of one barrel, as stated, acting to clear itself for the next firing charge by ejectingthe exploded cartridge and to load and re the other barrell and vice versa in continuous operation.

Secured to the top edge of the rack 14 the arm 29 to engage the opposite side and rim of the cartridge; the end of the plate 31 being pressed toward the end 30 of the arm v by a spring 33 positioned on a stud 34 rigidly secured in the arm 29 and freely projecting through the plate 31. Adjacent4 the v free ends of the arm and plate is a second stud 35 rigidly secured in the arm 29 and also freely projecting through the plate 31, the two studs acting as guides for the plate 31 in its pivotal relation with the forward arm 29.

Secured in .the end wall of the member 3 is a vertically disposed plate'36 having an angular surface 37 upon which the projecting end of the studV 35 rides as the breech bolt is moved back and forth in the guideways 10, the arm 29 and parts carried thereby being drawn downwardby a spring 38, the angular surface 37 acting to prevent excessive downward movement thereof andto lift the arm to presentthe loading mechanism in proper relation to the cartridge reels.

The cartridge supplying Kdevices are positioned adjacent the forward end of the form as an essential feature of the inven tion. rlfhe essential condition to be met is that the device must. be adapted to present the cartridges'in the rapid order required to serve the guns.

. The cartridge supplying device shown in the drawings comprises rotatable reels or drums 39 having radial Vextensions 40 and -recessed portions 40 in which the cartridges are supported. Traveling over the drum is the cartridge belt 41. The ends of thecartridges 42 therein extend beyond the projections 40 and coact therewith to draw the belt forward step by step to present the cartridges in a ppsition to be engaged by the loading mechanism. f t

The .drum 39 is actuated in theldlrectlon ilo v of the forward travel of the belt each time the gun is 'fired by mechanism connecting the drum'with the slide member 5. This connection may be of any suitable form. The construction shown consists of a bracket 43 attached to the frame l and having 'a Slot inwhich is slidably pivoted a pawl 45 normally drawn toward Ithe Jframe 1by a 'suitable sprin the slot and s ring being` of any suitab e construction. ne end of the pawl 45 is adapted to engage teeth 47 .se cured to the inner face of the drum 39. The other end of the pawl is connected to a link 48 which extends within the frame 1 and has a portion 49 which extends into the path of the end wall 8 of the slide member 5. rlhe link 48 isprovided with an arm 51 extending beyond the drum 39 andhaving secured thereto a tapered pin 52 adapted to bedrawn into holes 53( in the outer end wall of the drum 39,l the holes being spaced apart equally with the teeth 40. 4

Thus, when the slide 5 moves back and forth in the frame the drum will be actuated to advance the cartridge beltl step -by step to present the shells in position to be Withdrawn therefrom-and delivered to the gun barrel, the tapered pin 52 being drawn into one of the holes 53 to properly aline the drumand the shells thereon with the loader mechanism. As shownv in Fig: '2 ofthe drawings, the parts 30 and 31 of the loader mechanism engage the cartridge and upon the return movement o'f the mechanism withdraw the cartridge from the belt 41 and with the descending movement of the arm 29 present the cartrldge te the firing mechanism in the position shown in dotted lines in Fig. 1, from whence it is inserted into the barrehred, and theA shell ejected as described.

The operation of the loading mechanism is'as'follows: With the forward movement of the mechanism the pin 35 of the cartridge gripping member 31 rides upon the edge 37 of the plate 36, thus raising the cartridge engaging device and'causing the ends of the grippers 30 and 31 to Contact with the rim of the cartridge and to rise"thereover and grip the sides of the cartridge, the endsvof the grippers being drawn downwardly on opposite sides of the cartridge by tension of the spring 39, and the grippers held in contact with the cartridge by the pressure thereon ofthe spring 33. y

Upon the return'movement of the loader mechanism the cartridgeengaged lby the Agrippers will be withdrawn from the cartridge belt. and moved to4 av position in 'the slide member 5 -to be entered in the breech ofthe gun barrel.. v

With the closing movement of the firing mechanism the end of the cartridgel enters the barrel before the pin 35' contacts with thearm`36, thus when the pin engages the barrel 'to withdraw the empty cartridge prepara# arm and rides up on the edge 37 thereof the grippers 30 and 31 are forced to release the cartrid e which is then Jfully entered in the y the continued forward movement of the breech bolt.

Attached tothe forward end of the breech bolt 9 is a spring jaw 54 concentric ofthe firing pin 22. On the opposite side of the firing pin also concentric therewith and secured in the end wall of the breech bolt are bevel pins 55, the spring jaw and pins being adapted to engage the rim of .the-cartridge when the firing pin is released to discharge the gun and the breech bolt recedes tor f to reloading of the barrel.

ivotedy to the member by means of a stud 56 is a cartridge ejecting'arm-having an expandin 'finger 57 normally pressing against the side bfthe breech bolt. the breech bolt reedes afterv each firing operation carrying the discharged cartridge with it, the fin er 57 is released from conf tact with the side thereof, and, actuated by a spring 58, strikes the cartrid ea sharp blow on the sideythereof an ejects I"1t" through apertures in the outer wall of the member 5 and fra'me 1, which at'the moment ofjejectment of the, cartridge are in alinement, thereby `presenting an opening in lboth 95 walls through which the cartridge is ejected.y

Jwill' be engaged by the pawl 20 Vand the gun will be set` for ring. f f

A trigger mechanism is also provided whereby the guns when set as above de-4 scribed, may be started in automatic sequencel of firing perationl and each barrel may also be fire lsingly independent of the other barrel. rlFhe trlgger mechanism comprises a nger bar v 60 suspended from brackets 6l and 62, secured to the bottom of the frame l, by links' 63 and 64. Coperating with the slot .64 in the finger bar byl means of a stud is a vertically extending tripping member 66 which extends through aV slot 67 in the bottom of theframe l and.

ber 5 and breech bar 9. The member. 66

contacts withthe head 18 of the firing pin in4 .l

a manner to release the firing `pin when the rfinger bolt isdrawn to the rear and to prevent the accidental release of the firing pin 125 when the linger bolt is in forward position.

.The mechanism is normally heldin forward r or raised position bygvilzlension exerted theref n by alspring70.

' len the guns are to be When 811i fired continuously the trigger mechanism is y cresima held by the operator in the lower or inoperative position in which it has'no relation whatever with the firing pin and the guns are therefore free to fire automatically as log as the trigger is drawn back.

The operation of the latch 20,firing pin 15 and trigger member 66 is so timed that in setting the gun for firing the member66 engages the head of the firing pin slightly in advance -of the latch 2O with the result thatin the firing. operation, as when the `gun is set for firing the first shot, in a 'sequence of automatic operation, or when a single shot is to be fired, thelatch 20V releases, but the firing pin will still be retainedin firing position by the member 66 until the finger bar 60 is drawn' to the rear which will then release the firing pin to discharge the gun.

An-important feature of my invention is the improved means for cooling the barrels. 'lo this end-each barrel is provided with a Itube 71 attached at one end in any suitable manner to the frame, 1 and extending slightly beyond thegun barrel. The tube is provided with apertures 72 for the free introduction of air to the inner space of the tube surrounding the bairel. Secured to and surrounding the barrel is a cooling member 73 having fins or radially extending portions 73 whereby the maximumsurface exposure to the' air is obtained. V

With the firing ofthe gun the. barrel due [to the recoil thereof is rapidly actuated back and forth in the tube 71 and continuous suction and discharge of air takes place `through the apertures 72,/ the whole purpose and arrangement being such as that the maximum exposure of the barrel cooling surfaces and rapid circulation of cool air are obtained, the tendency of the barrels to eX- J cessivel heating being thus minimized.

ln .addition to the method of cooling the gun barrels above described which is substantially similar to the method employed on other types of automatic guns, l employ a novel arrangement for forcing air into the breech end of each barrela'each time' it is fired. For this`purpose l provide each barrel with an air compression cylinder 74 securedto the under side of the frame 1 in any suitable manner. rlifhe piston rod 75 and piston head v76 of each cylinder are connected to the slide members 5 by ver-I .tically extending arms 77 rigidly secured to theslides and operating throughslots 77 1n the bottom of the frame.

l One-end of the cylinder is also provided. with a chamber 78 having a piston head 79 movable therein. A spring acts to move vthe piston head'7 9 toward theopposite piston head J'76. When the' piston head 76 1s f actuated then air pressure between the piston heads acts, to forcethe head 79 against the spring 80 and across an aperture or po'rt 8.1 opening into the chamber 7 8.. Communiv the cylinders will be delivered under pressure It at points 84 in the side frame 1, as shown in Fig. 2 of the drawings. P

Pivoted oneach receiver or slide member 5 by studs 56and having one edge thereof riding against the inner side of the breech 75 bolts 9 is a reciprocating arm 85 having an air duct 86 extending therethrough. One end of this air duct is formed by a short tube 87 Secured in the arm 85 and extending'vertically through slots 88 in the frame 1 and 80 adapted to register with the discharge opening 84Cv 'of the tubes 83 and 83a when the respective barrels have reached their limit of movement from recoil action. The other end which may be designated as nozzle end 89 of 85 the air duct 86 opens into the extreme for- Y ward end of the arm and is immediately adjacent to the breech end of the barrel when the barrel is in its r'earmost position, an extension 90 of the slots 88 acting to rotate the 90 arm 85 labout its pivotal center, properly timed, to present the nozzle immediately adjacent the open end of the gun barrel and serving to force a. current' of air therethrough from the ycylinder, 74. Thus, a discharge@ of air fromvthe cylinder is forced through each barrel after each firing thereof. It will be-observed, however, that the'air in the cylinder is under pressure 'only during the recoil of the gun barrel. im@

To. increase the force of recoil of the gun barrels in order'that there may be` ample power for automatic operation of .the fload'- ing and firing mechanisms l provide the end of the gun barrel with anenlarged por- M5 tion 91 which acts as a piston head movable ina gas pressure chamber 92 in the front end of the cooling-'tube 71. F or this purpose the tube extends beyond the end of the barrel and iS provided with an end wall 93. u@

rlhe resulting gas, when the gun is disc charged, gathers in the chamber 92 and 'exercises pressure against the end wall 93 and pistonhead 91 of the gun barrel, the latter .1, 2 and 3 of the drawings.

1n Fig. 7 of the drawlngsgl have shown my invention applied to a typeL of guns 13125 known as gas operated guns. ln this form of construction the gun barrel is secured rigidly in the frame 1 and'a cylinder 101 is secured to the under side of the barrel in .any suitable manner.. The cylinder is pro- 1.86

vided with a` piston head 102 and piston rodl 103 which is connected at its oppositefend through a slot 104 in the bottom of the frame 1 to the receiver member 5 which is free to slide in the frame. Adjacent the front end It will be seen Ythat the gas pressure' in the*v cylinder 101 willbe exerted immediately the projectile passes the aperture 105- before the.

y projectile leaves the barrel. When the force of the reaction has been spent the 'cylinder is free to exhaust through the aperture 105 and the end of the gun barrel.

It will be understood that with fthe twin gun arrangement the pistons ofthe respecf'tive gas cylinders are properly timed with the loading and firing mechanism so that one piston moves idly on its return movement after each firing action, while the other piston is being actuated In this fo-rm of ga/s operated gun a sleeve member 106 having annular fin portions 107 is preferably used as part of the cooling system for the gun barrels. My improved system for injecting air 'into the breech end of the barrel will be equally adaptable, of course, to both forms of gun construction.

An important resultv is realized in both the recoil and gas operated guns in that the excessive force of the recoil is practically absorbed in the balanced relation of the mechanisms. The firing action is smooth and even and the guns,therefore, may be aimed and otherwise handled more effectually than is possible in single automatic guns in which theirecoil cannot be so controlled.

From the foregoing detail description of my invention itwill be apparentf that the underlying principle consists vin associating two or moreautomatic gun mechanisms in such a manner that the resultant force of discharging each of the guns will act respectively to load and fire another gun and to clear itself for reloading; that this Iforce may be transmitted to the loadingand firing mechanism by the recoil of the gun barrel, as is the principle in all recoil operated'guns, or by separate mechanism actuated in any suitable manner by the gases resultant from the firing of the guns; and that the firing of the guns when started will be automatic and in continuous sequence'of operation.

As stated, as`far as I am aware, I am the first to employ this principle and lfthe first, therefore, to realize in any form of gun construction the greatly increased speed in firing a gun controlled byfasingle operationp vas well as the general .increase ineffective# the appended claims.

ness of the guns due to the incidental advanta es of -reduced heating of the mechanism.

desire it Yto be understood, therefore, that the construction herein disclosed is but one form of approved application of the basic principle of my invention and that various changes may readily be made in the specific organization of the invention without departing from the principle or spiritthereof. I do not wish to be limited, therefore, to the general form of construction disclosed except as embodied and broadly set forth in Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent, is

1. In an automatic un, the combination, a frame, a plurality of longitudinally oper- .able barrels each having a receiver slideJ se- .cured thereto and operable in said frame, a

breech bolt operable in each of the receiver slides, a firing pin operable in each breech bolt, a rack and gear interposed between the opposite receiver slides and breech bolts, respectively, said -gears operating ,in unison and vsaid rcksbelng operable independently of each other, andv loading mechanism whereby the firing and recoil of one barrel will actuate said mechanisms in sequence to load and fire another barrel.

2. In an automatic gun, the combination, a frame, a plurality of barrels longitudinally operable in said frame, receiver mech -anisms secured to each of sai'd barrels,

breech bolts and iiring pins slidably superposed in each of the receiver mechanisms,

a rack and gear interposed between the opposite receiver slides and breech bolts, respectively, vsaid gears loperating in unison and said racks being operable independently of each other, and loading mechanism whereby the firing and recoil f /one barrel will actuate said mechanisms in sequence to load and fire another barrel.

3. In an automatic gun, the combination, a frame, la plurality of barrels longitudinally operablein said frame, receiver mechanisms secured to said barrels, breech bolts and firing pins `slidably superposed in the receive'mechanisms, racks secured to "and having limited longitudinal movementV on the opposite receiver mechanisms relative to -the movement of said mechanisms, racks secured 'to the opposite breech bolts, gears disposed between said racks', and loading mechanism whereby the ringand recoil of one barreLWill actuate said mechanismsvin sequence to load and fire anothergbarrel.

'4. In an automatic gun, the combination, a frame', a plurality of barrels longitudinally operable in said frame, receiver mechanisms' secured to each of 'saidl barrels, a,

breecli bolt'and firing pin slidably superigt posed in each of the receiver mechanisms, j

racks and gears of different diameters interposed between the opposite receiver mechanisms and breech bolts, respectively, whereby said mechanisms and the breech bolts have limited relative movement, and loading mechanism whereby the firing and recoil ofcured thereto and operable in said frame, a

breech bolt operable in each of the receiver slides, aring pin operable inthe breech bolts, racks and gears interposed between the opposite-receiver slides and breech bolts, respectively, a member to' lock the breech bolt to the receiver, and a latch movable with said receiver slide whereby the firing pin is rendered operative' and inoperative, respectively, and'loading mechanisml whereby the iii-ing and recoil of one barrel will actuate said mechanisms in sequence to load and lire another barrel.

" 6. ln an automatic gun, the combination,

a frame, a plurality of longitudinally op-' verable'barrels each having a receiver slide secured thereto and operable in said frame, a breech 'bolt operable in each of the receiver slides, a firing pin operable in the breech bolts, racks and gears interposed between the opposite receiver lslides and breech bolts, respectively, a member to lock the breech bolt to the receiver and a latch pivoted on the receiver slide, trigger mechanism coperating therewith whereby the firing pin is rendered operative and inoperative, respectively, and loading mechanism whereby the firing and recoil of one barrel will actuate said mechanisms in sequence to load and fire another barrel.

7. In an automatic gun, the combination, a frame,`a plurality of longitudinally operable barrels each having a receiver slide .secured thereto and operable in said frame,

a breech bolt operable in each ofthe receiver slides, a firing pin operable in the breech bolts, racks and gears interposed between the opposite receiver slides and breech bolts, respectively, loading mechanisms whereby the rin'g and recoil of one barrel will actuate said mechanisms in sequence to load and fire another barrel, and air compression cylinders coperating with said mechanisms .whereby a charge of air is forced into each barrel after the firing thereof.

8. ln an automatic gun, the combination, a'frame, a plurality of longitudinally operable barrelshaving receiver slidessecured thereto operable in said frame, loading and firing mechanisms comprising said receiver slides, breech bolts and firing pins, coperating parts interposed between the opposite Y sets thereof whereby the firing and recoil of one barrel will actuate said mechanisms in sequence to load and re another barrel, and l air compression cylinders coperating with said receiver slides whereby a charge of air is forced into each barrel after the firing thereof.

9L ln an automatic gun, the combination, a. frame, a plurality of longitudinally operable barrels' having receiver slides secured thereto operable in said frame, loading and firing mechanism comprising said receiver slides,l breech bolts and firing pins, cooperating parts interposed between the opposite sets thereoffwhereby the firing and recoil of one barrel will actuate said mecharnisms in sequence to load and fire another barrel, and air compression cylinders c0- operating with said receiver slides whereby the, firing of the barrels will cause a charge of air to be delivered therethrough.

l0. In an automatic gun, the combination, a frame, a plurality of longitudinally operable barrels having receiver slides secured thereto operable in said frame, loading and firing mechanism comprising said receiver slides, breech bolts and firing pins, coperating parts interposedbetween'the opposite sets thereof whereby the firing and recoil of one barrel will actuate said mechanisms in sequence to load and tire another barrel, and air compression cylinders, and air pas-- sages movable with the receiver slides, whereby a charge of air is forced into each barrel after the firing thereof.

1l. ln an automatic gun, the combination,

a frame, a plurality of'longitudinally operable barrels, loading and firing mechanism comprising receiver slides, breech bolts and firing pins, cooperating parts interposed between the opposite sets thereof whereby the firing and recoil of one barrel will actuate said mechanism in sequence to load and re another` barrel, and cylinders communicating with said barrels intermediate the loading and discharging ends thereofand having gas actuated pistons therein coperating with said mechanisms whereby the force of recoil thereon will be increased. y

l2. In an automatic'gun, the combination, a frame, a plurality of longitudinally operable barrels having receiver slides secured thereto operable in said frame, loading and firing mechanism comprising said receiver slides, breech bolts and firing pins,-cop erating parts interposed between the opposite sets thereof whereby the firing and recoil of' one barrel will actuate said mechanisms in sequence to' load and fire another barrel, and sleeves having a plurality of outwardly extending circumferential fins formed in the periphery thereof telescoping said barrels, and an apertured air chamber telescoping each of said sleeves whereby said barrels are cooled after the firing thereof.l

lntestimony whereof, I alii'x my signalll() 

